Remove gsheets related code

[jingcheng16]

Product Description

Technical Summary

We no longer plan to develop gsheet feature. So in this PR I remove all the related code.
Ticket: https://dimagi.atlassian.net/browse/SAAS-16161

Feature Flag

Safety Assurance

Safety story

The deleted code are not referenced anywhere

Automated test coverage

QA Plan

No

Migrations

• The migrations in this code can be safely applied first independently of the code since the code is not being used (there would be 500 errors if the removed URL patterns were accessed).

Rollback instructions

• This PR can be reverted after deploy with no further considerations
  I didn't write reverse code in migration because I don't expect this PR to be reverted

Labels & Review

• Risk label is set correctly
• The set of people pinged as reviewers is appropriate for the level of risk of the change

[jingcheng16]

Checked on production, the deleted sql model don't have any data. So no need to run migration before deploy.

[millerdev]

Looks like another make requirements is needed to fix tests.

diff --git a/requirements/dev-requirements.txt b/requirements/dev-requirements.txt
index eea7e9f..2656028 100644
--- a/requirements/dev-requirements.txt
+++ b/requirements/dev-requirements.txt
@@ -294,7 +294,6 @@ gnureadline==8.1.2
 google-api-core==2.11.0
     # via
     #   firebase-admin
-    #   google-api-core
     #   google-api-python-client
     #   google-cloud-core
     #   google-cloud-firestore

Otherwise this looks good to me.

[jingcheng16]

@millerdev Weird, I just run make requirements again and there is no new changes...

[orangejenny]

Reviewed last two commits